5 

/4.G6-. 


AMERICAN     ASSOCIATION 
OF  PETROLEUM  GEOLO.C 


BULLETIN  OF 

ILLINOIS  COAL  MINING  INVESTIGATIONS 

COOPERATIVE  AGREEMENT 

Issued  bi-monthly 


VOL.1 


September,  1914 


No.  4 


State  Geological  Survey 

Department  of  Mining  Engineering,  University  of  Illinois 

U.  S.  Bureau  of  Mines 


BULLETIN  7 

Coal  Mining  Practice 

IN 


District  II 


BY 
S.  O.  ANDROS 


Published  by 

University  of  Illinois 

Urbana,  Illinois 


(Entered  as  second-class  matter,  June  1,  1914,  at  the  postoffice  at  Urbana,  Illinois,  under 
the  Act  of  August  24,  1912.) 


The  Forty-seventh  General  Assembly  of  the  State  of  Illinois, 
with  a  view  of  conserving  the  lives  of  the  mine  workers  and  the 
mineral  resources  of  the  State,  authorized  an  investigation  of  the 
coal  resources  and  mining  practices  of  Illinois  by  the  Department  of 
Mining  Engineering  of  the  University  of  Illinois  and  the  State 
Geological  Survey  in  co-operation  with  the  United  States  Bureau  of 
Mines.  A  co-operative  agreement  was  approved  by  the  Secretary  of 
the  Interior  and  by  representatives  of  the  State  of  Illinois. 

The  direction  of  this  investigation  is  vested  in  the  Director  of 
the  United  States  Bureau  of  Mines,  the  Director  of  the  State 
Geological  Survey,  and  the  Head  of  the  Department  of  Mining 
Engineering,  University  of  Illinois,  who  jointly  determine  the 
methods  to  be  employed  in  the  conduct  of  the  work  and  exercise 
general  editorial  supervision  over  the  publication  of  the  results,  but 
each  party  to  the  agreement  directs  the  work  of  its  agents  in  carrying 
on  the  investigation  thus  mutually  agreed  on. 

The  reports  of  the  investigation  are  issued  in  the  form  of  bul- 
letins, either  by  the  State  Geological  Survey,  the  Department  of 
Mining  Engineering,  University  of  Illinois,  or  the  United  States 
Bureau  of  Mines.  For  copies  of  the  bulletins  issued  by  the  State 
and  for  information  about  the  work,  address  Coal  Mining  Investiga- 
tions, University  of  Illinois,  Urbana,  111.  For  bulletins  issued  by 
the  United  States  Bureau  of  Mines,  address  Director,  United  States 
Bureau  of  Mines,  Washington,  D.  C. 


ILLINOIS  STATE  GEOLOGICAL  SURVEY 


3  3051  00006  3697 


ILLINOIS 

COAL  MINING  INVESTIGATIONS 

COOPERATIVE  AGREEMENT 


State  Geological  Survey 

Department  of  Mining  Engineering,  University  of  Illinois 

U.  S.  Bureau  of  Mines 

AMERICAN    ASSOCIATION 

OF  PETROLEUM  GEOLOGISTS 

BULLETIN  7 

Coal  Mining  Practice 

IN 


District  II 


BY 
S.  O.  ANDROS 


Urbana 

University  of  Illinois 

1914 


1 


J? 


7^ 


CONTENTS 


PAGE 

Introduction      7 

Description    of    bed 9 

System    of    mining 10 

Ventilation     13 

Blasting      14 

Timbering     17 

Haulage     is 

Hoisting     1!) 

Preparation     of    coal 21 


TABLES 


No.  PAGE 

1.  Comparative  statistics  for  District  II  and  the  State  for  the  year  ended  June  30,  1912  8 

2.  Analyses   of  No.   2   coal   in   Districts  I   and   II 9. 

3.  Pressures    developed    by    face    samples    in    explosibility    apparatus , 10 

4.  Dimensions    of    workings    in    feet ,  .  .  .  .  12 

5.  Per    capita    production    of    coal 13 

6.  Ventilating     equipment 14 

7.  Blasting      17 

8.  Timbering     ....'. 18 

9.  Haulage 19 

10.  Hoisting    '.'....' 20 

11.  Sizes  of  coal  made 21 

12.  Tipple    equipment     21 

13.  Power   plant   equipment 22 


ILLUSTRATIONS 


PAGE 

Fig.  1.     Map   showing  area  of  District   I Frontispiece 

Fig.  2.      Arching    of    top    coal    in    entries 11 

Fig.  3.     Method   of  shooting   after   hand   snubhing 15 

Fig.  4.     Method  of  shooting  after  chain  machine ]  5 

Fig.  5.     Method  of  shooting  after  puncher  machine 16 

Fig.  6.     Timbering   in   entries  under  shale   roof 17 


Fig.   1.     Map   Showing  the   Area    (Shaded)    of  District  It 


BULLETIN  OF 


ILLINOIS  COAL  MINING  INVESTIGATIONS 
COOPERATIVE  AGREEMENT 

Issued  bi-monthly 

VOL.  I  SEPTEMBER,  1914  No.  4 

COAL  MINING  PRACTICE  IN  DISTRICT  II 

By  S.  O.  ANDROS 


INTRODUCTION 

District  II  of  the  Illinois  Coal  Mining  Investigations,  as  shown 
in  fig.  1,  comprises  those  mines  in  Jackson  County  which  produce 
coal  from  bed  2  of  the  Illinois  Geological  Survey  correlation.  A 
detailed  description  of  the  districts  into  which  the  State  has  been 
divided  and  the  method  of  collecting  the  data  upon  which  this  bul- 
letin is  based  is  contained  in  Bulletin  1,  "A  Preliminary  Report  on 
Organization  and  Method." 

The  physical  characteristics  of  the  coal  bed  and  the  mining 
practice  of  this  district  differ  from  those  in  districts  in  northern  and 
northwestern  Illinois,  where  bed  2  is  also  mined.  The  district  prop- 
erly cannot  be  considered  a  part  of  any  other  in  southern  Illinois 
because  in  the  other  southern  districts  either  bed  5  or  bed  6  is  mined. 
Therefore,  it  is  necessary  to  treat  this  restricted  area — although  it 
has  few  mines  and  a  small  production — in  a  separate  bulletin. 

The  first  historical  record  of  coal  mining  in  Illinois  refers  to  a 
flatboat  load  of  coal  mined  in  1810  at  a  point  on  the  Big  Muddy 
River  in  Jackson  County.  One  of  the  eight  mines  now  operating  in 
the  district  was  opened  about  forty  years  ago ;  the  other  seven  have 
been  in  operation  from  seven  to  nine  years.  The  total  production 
of  coal  during  the  year  ended  June  30,  1912,  was  500,102  short 
tons,  0.9  per  cent  of  the  total  production  of  the  State.  This  coal 
was  nearly  all  undercut,  479,779  tons — 95.9  per  cent — of  the  total 
output  having  been  mined  by  machines.  Machine  mining  has 
resulted  in  a  low  powder  consumption.  During  the  year  ended 
June  30,  1912,  4,500  kegs  of  powder,  0.3  per  cent  of  the  total  for  the 
State,  were  used  for  blasting  coal  in  the  district. 

The  mines  employed  an  average  of  750  men  for  an  average  of 
156  days. 

Table  1  gives  comparative  statistics  for  the  District  and  for 
the  State  during  the  year  ended  June  30,  1912. 


COAL    MINING    INVESTIGATIONS 


Table  1. — Comparative  statistics  for   District  II  and   the  State  for  the 
year  ended  June  jo,  IQI2& 


District 

State 

Per  cent 

500,102 

57,514,240 

0.9 

479,779 

25,550,019 

1.9 

3,206 

359,464 

4,566 

1,313,448 

0.3 

156 

160 

750 

79,411 

0.9 

117,000 

12,705,760 

0.9 

97 

7,049 

1.3 

653 

72,362 

0.9 

441 

43,308 

0.8 

6.7 

10.3 

4.3 

4.5 

33.0 

50.9 

4.9 

4.9 

7.3 

6.1 

0 

180 

8 

800 

1.0 

35.7 

45.5 

25.0 

26.3 

10.7 

10.1 

62,513 

71,893 

Total  production 

Tons  mined  by  machine 

Average  daily  tonnage  

Kegs  of  powder  used  in  blasting  coal 

Days  of  active  operation 

Total  employees 

Days  work  performed 

Surface  employees  . 

Underground  employees 

Average  number  of  face  workers  (miners, 
loaders,  and  machine  men)b 

Underground  employees  per  each  surface 
employee 

Tons  mined  per  day  per  employee  

Tons  mined  per  day  per  surface  employee  .  . 

Tons  mined  per  day  per  underground  em- 
ployee  

Tons  mined  per  day  per  face  workerb 

Fatal  accidents 

Non-fatal  accidents 

Per  cent  from  falling  coal  or  rock 

Per  cent  from  pit-cars 

Injuries  per  1000  employees  

Tons  mined  to  each  man  injured 


Compiled  from  Thirty-first  Annual  Coal  Report  of  Illinois. 
Shipping  mines  only. 


Thanks  are  due  to  the  operators  of  this  district  for  granting 
permission  to  inspect  their  mines  and  to  the  superintendents  and 
mine  managers  who  assisted  in  collecting  data.  Special  acknowledg- 
ments should  be  made  to  Mr.  John  McClintock,  State  Mine 
Inspector,  and  to  Mr.  Thomas  Little,  former  State  Mine  Inspector, 
for  their  valuable  assistance. 


DESCRIPTION    OF    COAI.    BED 

DESCRIPTION  OF  COAL  BED 


Bed  2  in  Jackson  County  has  only  a  shallow  cover,  the  coal 
lying  at  depths  varying  from  25  to  160  feet  at  different  mine  loca- 
tions. A  characteristic  feature  of  the  bed  is  its  division  into  two 
benches  by  a  gray  laminated  shale  band  varying  in  thickness  from 
-J  inch  to  36  feet.  Where  this  parting  is  thick  the  lower  bench  has 
sometimes  been  called,  erroneously,  bed  1.  The  bottom  bench  varies 
in  thickness  from  3^  to  4  feet,  averaging  3f  feet.  The  top  bench 
averages  2  feet. 

The  bed  contains  few  nodular  concretions  of  iron  pyrites,  but 
has  a  layer  of  bone  2  to  3  inches  thick,  generally  next  to  the  floor. 
This  floor  in  most  places  is  sandstone,  but  in  sections  is  shale  or  fire- 
clay.    The  coal  shows  a  pronounced  cleavage,  northeast  to  southwest. 

The  chemical  composition  and  calorific  value  of  "No.  2  coal  as 
found  in  District  II  vary  considerably  from  those  of  the  coal  of  the 
same  bed  in  District  I,  comprising  Bureau,  Grundy,  LaSalle,  Mar- 
shall, Putnam,  Stark  and  Will  Counties.  A  comparison  between  the 
coals  of  these  districts  is  given  in  Table  2. 


Table  2.— A 

nalyses  of  No.  2  coal  in  District  I  and  II 

\ 

-l-> 

"a 

£ 

w 
6 

Proximate  analysis  of  coal: 
1st;  "As  rec'd,"  with  total 
moisture 

2nd;  "Dry,"  or  moisture  free 

pq 

o 
'£ 

s 

S-c 

'o 

~   u 

>  c 

II 

in 

< 

5m 

I 

33 

16.18 
Dry 

38.83 

46 .  33 

37.89 
45.21 

7 .  08 
8.45 

2.89 
3.45 

10981 
13101 

1452S 

II 

15 

9.28 
Dry 

33.98 
37.46 

51.02 
56.24 

5.72 
6.30 

1.29 
1.42 

12488 
13765 

14818 

a.     Analyses  made  by  J.  M.  Lindgren  under  the  direction  of  Prof.  S.  W.  Parr 

The  superiority  of  the  coal  in  District  IF  is  apparent.  It  has 
less  volatile  matter,  more  fixed  carbon,  less  ash  and  moisture,  and  a 
higher  calorific  value  than  the  coal  of  District  I. 

The  small  amount  of  gas  given  off  by  the  bod  is  usually  found 
only  in  abandoned  workings. 

Where  the  parting  is  thin  and  the  two  benches  are  united,  the 
roof  over  the  coal  is  a  hard  gray  shale,  but  where  the  parting  is  thick 
and  only  the  lower  bench  is  worked  the  parting  becomes  the  roof. 


10 


COAL    MINING    INVESTIGATIONS 


Where  this  parting  is  a  light  gray  shale  it  is  easy  to  support ;  where 
it  is  dark  colored  it  slakes  much  on  exposure  to  the  air. 

In  all  the  mines  of  this  district  numerous  small  faults  occur 
and  horses,  usually  of  a  hard  dark  gray  micaceous  sandstone,  are 
found  in  the  vicinity  of  the  faults. 

The  presence  in  places  of  a  quicksand  deposit  about  thirty  feet 
below  the  surface  has  a  marked  effect  on  surface  subsidence  after 
roof-caves. 

Table  3.— Pressures  developed  by  face  samples  in  explosibility  apparatus 


District 

No.  samples 

Pressure  in  pounds  per  square 
inch  at  2192°  F 

I 

11 

8.40 

II 

5 

5.88 

III 

5 

7.81 

IV 

17 

7.70 

y 

7 

7.11 

VI 

16 

5.95 

VII 

24 

7.00 

VIII 

6 

8.93 

The  face  samples  of  coal  from  this  district  when  ground  to  200- 
me'sh  size,  air-dried,  and  tested  in  the  explosibility  apparatus  at  the 
Urbana  laboratory  show  less  explosibility  than  the  coal  of  any  other 
district,  although  the  rib  dust  of  some  other  districts  is  less  explosible 
on  account  of  an  admixture  of  fine  shale  dust.  In  Table  3  are  com- 
pared pressures  developed  in  the  explosibility  apparatus  for  the 
various  districts  in  Illinois. 

SYSTEM  OF  MIOTMJ 


Although  the  coal  bed  in  this  district  has  a  thin  cover  all  mines 
are  opened  by  shafts.  There  are  no  drifts,  slopes  or  strippings. 
Seven  of  the  eight  mines  are  worked  according  to  the  double  entry 
room-and-pillar  system ;  the  panel  system  with  triple  main  entries, 
maintaining  one  of  the  air-courses  for  a  traveling  way,  is  used  in  the 
other  mine. 

The  variable  shale  parting  in  the  bed  gives  rise  to  two  sets  of 
conditions.  Where  the  parting  is  less  than  4  inches  thick  the  two 
benches  of  the  bed  are  worked  as  one  and  the  working  faces  in  rooms 
and  entries  are  6  to  7  feet  high  in  places.  Where  the  parting  is  over 
4  inches  thick  the  lower  bed  only  is  mined  and  the  parting  becomes 
the  mine  roof.     The  lower  bench  averages  3f  feet. 

Where  both  benches  are  worked  and  the  bed  is  over  6  feet  thick 
only  the  lower  6  feet  of  coal  is  mined,  8  to  12  inches  of  top  coal  being 


MINING      PRACTICE 


11 


left.  The  shale  roof  disintegrates  on  exposure  to  the  air,  but  top 
coal  is  not  affected  by  temperature  and  remains  intact  for  many 
years.     Where  it  is  possible  to  leave  top  coal  in  entries  the  roof  is 


arched,  as  shown  in  fig.  2. 


In  driving  entries  the  lower  3  feet  of 


Fig.  2.      Arching:  of  Top  Coal   in   Entries. 


coal  is  drilled  and  shot  off  the  solid;  but  all  arching  in  the  upper 
3  feet  is  hand  sheared,  with  the  result  that  the  top  coal  remains  per- 
manently in  place  and  requires  no  support  except  where  fractured 
by  slips.  Top  coal  is  arched  in  several  districts  in  Illinois,  but 
usually  the  arch  is  roughly  formed  by  shooting,  and  the  top  coal  is 
often  fractured  by  the  shots. 

Where  the  two  benches  of  the  bed  are  united  but  the  coal  is 
not  over  (\  feet  thick  the  full  thickness  of  the  bed  is  mined,  and  the 
gray  shale  overlying  the  coal  becomes  the  roof.  In  rooms  2  to  4 
inches  of  this  shale  are  drawn  or  come  down  with  the  coal.  Where 
the  lower  bench  only  is  worked,  by  the  terms  of  the  Illinois  State 
Agreement  between  the  Illinois  Coal  Operators'  Association  and  the 
United  Mine  Workers  of  America  the  miner  brushes  14  inches  of  roof 
over  roadways  in  rooms.  The  width  of  brushing  varies  from  5  to  8 
^oot.     The  gob  obtained  is  laid  along  both  sides  of  the  track. 

Only  one  of  the  mines  examined  operates  with  any  regular 
dimensions  of  rooms  and  pillars.  At  all  of  the  others  pillar-gouging 
is  permitted.     In  one  mine  the  coal  of  the  main  barrier  pillar  was 


12 


COAT.    MINING    INVESTIGATIONS 


token  out,  leaving  an  insufficient  pillar  to  protect  the  main  entry. 

The  main  and  cross  entries  vary  in  width  from  S  to  9  feet.  In 
the  one  mine  operating  on  the  panel  system  the  width  of  room  entry 
is  9  feet;  16  rooms  being  turned  off  each  entry.  No  attempt  is  made 
to  draw  pillars  except  in  the  panel  system  mine  and  there  when  two 
adjacent  rooms  are  driven  up,  the  room  pillar  is  drawn,  where  it 
has  not  been  gouged,  by  taking  a  6-foot  slice  off  each  rib.  It  is  said 
that  one-half  of  the  pillar  coal  is  thus  recovered. 

Th*e  cleat  in  the  bed  is  well  marked,  but  in  the  panel  mine  alone 
is  advantage  taken  of  the  cleavage  to  drive  entries  on  the  butt  of  the 
cleat,  and  rooms  on  the  face. 

Numerous  horses  of  micaceous  sandstone  and  small  faults  cause 
difficulty  in  mining  and  add  considerably  to  the  cost  of  coal  pro- 
duction. In  places  these  horses  are  of  great  length,  one  of  them 
extending  throughout  a  mine.  In  driving  through  these,  blasting 
with  dynamite  is  done  off  the  solid. 

Table  4  gives  dimensions  of  workings  at  each  mine  examined. 


Ta 

BLE 

4.- 

— Dimensions 

of 

workings 

w  /eg/ 

00 

Entry 
width 

Entry 
pillar 
width 

Room 

'a 

Room-neck 

a 

■5 

£ 

p  * 

o 

x 

£ 

^  n 

£  E 

o 

*o 

%% 

c* 

<U  o 

"o 

X 

a 

s>  & 

X 

o 

X 

X 

X 

S-B 

c^ 

u  d 

CtI 

6 

ft 
Q 

t/3 

C/2 

2 

o 
O 

C 

"3 

2 

o 
u 

O 

Sft 

bo 
a 

C 

■5| 
11 

12 

125 

Room-and- 

pillar 

8 

8 

12 

12 

20 

24 

150 

18 

8 

10 

45°  to  right 
and  left 

20 

8 

44 

13 

114 

Panel 

9 

9 

20 

20 

30 

24 

250 

20 

9 

4 

45°  to  left 

20 

9 

55 

14 

135 

Room-and- 

pillar 

8 

8 

18 

18 

28 

250 

22 

8 

12 

45°  to  left 

22 

8 

46 

15 

160 

Room-and- 

pillar 

8 

8 

18 

18 

20 

25 

240 

17 

8 

10 

45°  to  right 
and  left 

20 

10 

49 

To  obtain  full  room  width  in  two  mines  room  necks  are  widened 
at  an  angle  of  45  degrees  to  the  left  only ;  in  the  others  the  widening 
is  done  at  45  degrees  both  to  the  right  and  left.  Where  the  roof  falls 
under  quicksand  deposits,  sand  and  water  are  admitted.  In  one 
mine  approximately  1,000,000  gallons  per  24  hours  flow  into  the 
mine  through  caves.  This  water  is  pumped  out  through  drill  holes 
by  two  automatically-started  electric  turbine  pumps  of  250  gallons 
per  minute  capacity;  two  stationary  electric  pumps  of  180  gallons 
per  minute  capacity;  and  five  portable  electric  pumps  discharging 
70  gallons  per  minute.  Water  flows  into  some  mines  through  chan- 
nels in  the  floor  under  the  coal.     The  caves  under  quicksand  deposits 


MINING     PEACTICE 


13 


often  bring  about  surface  subsidence,  one  of  18  feet  having  been 
reported. 

The  laborers  in  the  district  are  principally  of  three  nationalities : 
American,  Italian  arid  Negro,  the  majority  being  Americans. 
Although  nearly  all  the  coal  produced  is  undercut,  the  per  capita 
production  of  all  classes  of  employees  iu  the  district  is  low  as  com- 
pared with  that  in  all  other  districts  of  the  State  combined. 
(Table  5.) 

Table  5. — Per  capita  production  of  coal 


Mine  No. 


Average  daily  tonnage 

Number  employees 

Surface  employees 

Underground  employees 

Face  workers  (miners,  loaders  and 

machine  men)     

Underground   employees  per  each 

surface  employee 

Tons  of  coal  a  day  per  employee .  . 
Tons    of    coal   a   day  per  surface 

employee 

Tons  of  coal  a  day  per  underground 

employee 

Tons    of    coal     a     day    per    face 

workerb 


12 


150 

54 

4 

50 


12.5 

2.8 


37.5 
3.0 

4.1 


13 


1300 

255 

50 

205 

152 

4.1 
5.1 

26.0 

6.3 

8.5 


14 


300 
93 
13 

80 

56 

6.2 
3.2 

23.1 

3.8 
5.4 


15 


800 

196 

26 

170 

130 

6.53 
4.1 

30.8 

4.7 

6.2 


Dist- 
tricta 


3206 

750 

97 

653 

441 

6.7 
4.3 

33.0 

4.9 

7.3 


All  other 

districts 

combined* 


356,258 

78,661 

6,952 

71,709 

52,877 

10.3 
4.6 

51.3 

5.0 

6.8 


a.  For  the  year  ended  June  30,  1(.H2. 

b.  Shipping  mines  only. 

The  district  has  been  fortunate  in  having  but  few  fatal  acci- 
dents, but  the  number  of  non-fatal  accidents  is  greater  than  is  war- 
ranted by  the  coal  output.  The  sum,  however,  of  both  fatal  and 
non-fatal  accidents  is  consistent  with  this  output,  which  for  the  year 
ended  June  30,  1912,  was  0.9  per  cent  that  of  the  State.  In  this 
year  0.8  per  cent  of  the  combined  fatal  and  non-fatal  accidents  in  the 
State  occurred  in  District  I  I. 

VENTILATION 


The  ventilation  of  the  mines  in  this  district  presents  no  difficult 
problems,  and  the  ventilating  equipment  is  suitable  to  their  capacity. 
(Table  6.) 

The  largest  quantity  of  air  delivered  by  the  ventilating  fan  at 
any  mine  examined  was  50,000  cubic  feet  a  minute;  a  greater  quan- 
tity is  unnecessary  because  gas  is  not  present  in  large  quantities,  and 
also  because  comparatively  few  men  are  employed  in  the  present 
workings.     Two  of  the  mines  examined  had  blowing  fans,  and  two 


14 


COAL    MINING    INVESTIGATIONS 


•exhaust.  Sling  psychrometer  readings  in  rooms  for  October,  1913, 
showed  a  relative  humidity  of  mine  air  varying  from  90  to  100  per 
cent.  The  return  air  at  one  mine  had  100  per  cent  relative  humidity, 
as  shown  by  hygrometer  readings  reported  daily  by  the  mine  officials 
from  February  11,  1912,  to  February  16,  1913. 


Table  6. — 

Ventilating  equipment 

No. 

Depth  of 
air-shaft 

Size  in  feet  of 

air-shaft  in 

clear 

Type  of  fan 

Diameter 
of  fan  in  feet 

Width  of 

blade  in 

feet 

12 
13 
14 
15 

125 
114 
135 
160 

8  by  10 

9  by  20 

±y2  by  iy2 

8      by  12 

Paddle  wheel1 
Robinson 
Paddle  wheel 
Robinson 

16 

10 

16 

6 

4 
3 
4 

V/2 

1.    Paddle  wheel  refers  to  straight  blade  type  of  fan;  often  home  made. 

~Mo  underground  fires  of  consequence  have  occurred  in  the  dis- 
trict. Seepage  water  makes  unnecessary  the  sprinkling  of  roadways. 
The  underground  fire  liability  is  further  decreased  by  the  stabling 
of  mules  on  the  surface. 

In  mine  9  of  the  Big  Muddy  Coal  and  Iron  Company  danger 
of  underground  fire  is  reduced  to  a  minimum  by  prohibiting  the 
storing  of  oil  in  the  run-around.  The  daily  supply  taken  below  is 
stored  in  a  small  room  driven  in  the  rib  near  the  shaft  and  closed  by 
a  fireproofed  door.  The  oil  is  also  heated  here  by  steam  coils.  This 
mine  has  one  intake  haulage  entry  and  two  return  air-courses ;  is 
operated  on  the  panel  system :  and  is  one  of  the  two  mines  of  the 
district  in  which  have  been  placed  concrete  stoppings  on  the  perma- 
nent entries.  These  stoppings  are  built  with  concrete  blocks  5  inches 
thick,  having  an  exposed  surface  8  by  20  inches.  The  blocks — made 
on  the  surface  with  1  part  cement  and  0  parts  cinders — cost  6  cents 
each  delivered  at  the  pit  mouth. 

Stoppings  of  untamped  gob  in  two  of  the  mines  examined  gave 
low  ventilating  efficiency  because  of  the  large  amount  of  air  short- 
circuiting  through  leaks. 

Although  the  dust  of  the  district  is  not  highly  explosive  the  dan- 
gerous practice,  observed  in  one  mine,  of  leaving  machine  cuttings  at 
the  face  while  shots  are  being  fired  should  be  prohibited. 

At  one  mine  a  brick-lined  air-shaft  has  recently  been  sunk.  The 
air-shafts  at  all  other  mines  are  timber  lined. 

BLASTING 


In  District  II  a  greater  proportion  of  the  coal  mined  is  under- 
cut bv  machines  than  in  anv  other  district  of  the  State.     During  the 


MINING      PRACTICE 


15 


year  ended  June  30,  1912,  the  district  produced  500,102  tons  of  coal 
of  which  amount  470,779  tons,  95.9  per  cent  of  the  total  production, 
were  mined  by  machines.  Every  mine  in  the  district  except  two 
local  mines  has  undercutting  machines  installed. 


PLAN 

Fig.   3.     Method   (if   Shooting  After   Hand    Snubbing 

At  three  of  the  four  mines  examined  puncher  machines  operated 
by  compressed  air  are  used;  in  the  other  mine  the  coal  is  undercut 
with  electric  chain  machines.     The  usual  method  of  supplying  air  to 


PLAN 
Fig.   4.      Method   of   Shooting   After   Chain    Machine 


the  puncher  machines  is  to  carry  it  from  the  compressor  down  the 
shaft  and  through  the  main   entry  in  a  4-inch   pipe,   reducing  to  a 


16  COAL    MINING    INVESTIGATIONS 

2-inch  in  the  cross  entries  and  to  1^  inches  from  the  cross  entries  to 
the  faces  of  rooms. 

The  large  percentage  of  undercut  coal  accounts  for  the  use  of  a 
comparatively  small  amount  of  powder.  During  the  year  ended 
June  30,  1912,  the  district  while  producing  0.9  per  cent  of  the  out- 
put of  the  State  used  4,566  kegs  of  powder  for  blasting  coal,  only  0.3 
per  cent  of  the  total  for  the  State. 

Size  FF  black  powder  is  used  exclusively  in  blasting  coal.  The 
use  of  this  small  grained  powder  results  in  a  low  percentage  of  lump 
coal.  At  the  mines  examined  the  per  cent  of  coal  over  1^  inches 
varies  from  50  to  70.  The  number  of  tons  of  coal  gained  per  keg  of 
powder  varies  from  100  to  150  and  the  output  per  machine  from 
35  to  150  tons. 

In  the  mines  of  this  district  the  provision  of  the  State  law  in 
regard  to  material  for  tamping  holes  is  not  observed  carefully: 
machine  cuttings  in  dummies  are  often  used.  Tn  general  the  length 
of  holes  drilled  is  consistent  with  the  depth  of  undercutting  and  the 
thickness  of  the  bed. 


I 


FRONT 


SIDE 


PLAN 

Fig.   5.     Method   of   Shooting  After  Puncher  Machine 

The  general  methods  of  placing  holes  in  the  face  are  shown  in 
Figs.  3,  4  and  5.  Three  holes  constitute  a  round  at  every  mine 
examined.  The  only  variation  of  method  is  in  the  distance  below 
the  roof  at  which  the  center  hole  is  drilled. 

Koof  brushing,  which  is  done  with  black  powder,  is  easily 
accomplished,  one  hole  about  2  feet  long  bringing  down  4-J  linear 
feet  of  roof. 

Table  7  gives  blasting  data  for  each  mine  examined.     All  of  the 


MINING      PRACTICE 


17 


figures  for  the  percentages  of  lump  coal  over  1J  inches  were  obtained 
from  the  books  of  the  companies. 


Table  ' 

r. — Blasting 

No. 

Kind  of  machine 

Tons  a  day 

per 

machine 

Length  of 
holes  in 
feet 

Tons  of  coal 
per  keg  of 
powder 

Powder  cost 
in  cents  per 
ton  of  coal 

Per  cent  of 
lump  over 
134  inches 

12 
13 
14 
15 

Compressed  air  puncher 
Electric  chain 
Compressed  air  puncher 
Compressed  air  puncher 

4 

5 

4^ 

35 
150 

4 
6 

4% 

5V2 

100 
115 
150 
125 

1.8 

1.7 
1.2 
1.4 

70 
50 

See  foot  notea 
60 

55  over  \Yi  inches 


TIMBEKIKG 


Where  the  two  benches  of  the  bed  are  united  and  the  coal  is 
over  6  feet  thick,  top  coal  is  left  up  in  entries  and  the  roof  is  arched. 
(Fig.  2.)  ~No  timber  is  used  in  entries  under  top  coal  except  where 
it  is  broken  by  slips. 

When  the  lower  bench  only  is  mined  the  roof  is  supported  by 
three-piece  timber  sets  having  8-inch  crossbars  and  6-inch  legs. 
White  oak  is  generally  used  for  entry  timbering.  In  a  few  instances 
the  legs  of  the  timber  set  are  placed  in  hitches  cut  in  the  rib.  (Fig.  6.) 
In  one  mine  80-pound  steel  crossbars  with  T  section  are  used  on 
white  oak  legs  under  bad  roof  on  the  main  haulage  entry  and  white 
oak  crossbars  in  all  other  entries. 


Fig. 


Timbering  in   Entries   Under   Shale   Roof 


18 


COAL    MINING    INVESTIGATIONS 


The  roof  in  rooms  not  working  under  top  coal  is  difficult  to 
support.  Roadways  to  the  face  are  provided  by  brushing  the  roof  in 
low  coal  and  throwing  the  gob  alongside  the  track.  Propping 
expense  is  heavy;  the  number  of  props  per  100  square  feet  of  roof 
varying  from  4.8  to  7.5  is  greater  than  in  any  other  district  in 
Illinois.  (See  Table  8.)  These  figures  were  obtained  by  counting 
the  number  of  props  in  100  linear  feet  of  typical  rooms  the  widths 
of  which  had  been  measured.  Room  propping  is  carefully  done  in 
the  district,  especially  in  one  mine,  where  systematic  propping  is 
enforced.     At  this  mine,  where  pillars  are  drawn  by  cutting  a  slab 

6  feet  wide  from  each  rib,  two  extra  rows  of  props  are  set  between 
the  track  and  the  right-hand  rib  to  support  the  roof  as  the  pillar  is 
drawn. 

The  operators  of  the  district  often  are  able  to  get  30  per  cent 
of  white  oak  timber  in  each  shipment  of  props.  Both  split  and  round 
props  with  a  diameter  of  4-J  inches  at  the  small  tip  are  used  at  each 
mine  examined.     Their  length  varies  from  4  feet  under  low  coal  to 

7  feet  when  both  benches  of  the  bed  are  united. 

The  total  timbering  cost,  including  room  propping  and  entry 
timbering,  varies  from  5  to  8  cents  per  ton  of  coal  mined. 

All  shafts  in  the  district  except  one — which  has  a  brick  lining — 
have  timber  linings,  as  they  were  sunk  before  the  passage  of  the 
State  law  requiring  new  shafts  to  be  iireproofed. 

Table  8. — Timbering 


Total  timber  cost 
in  cents  per  ton 
of  coal. 

Room  Props 

No. 

No.  per  100 
square  feet 
of  roof 

Cost  in  cents 
per  1C0  square 
feet  of  roof. 

^    . 

tun  QJ 

■S.3 
31 

c  o 

12 
13 

8 

6.6 
4.8 
7.5 
5.5 

26.4 
33.6 
33.8 
38.5 

4 

7 

7 

18 
18 
18 
24 

33 
15 

14 

25 

15 

30 

HAULAGE 


Conditions  in  the  district  are  not  favorable  to  low  haulage  costs. 
Two  of  the  mines  examined  had  modern  equipment,  but  in  only  one 
was    sufficient    attention    paid    to    easing    curves    and    maintaining 


MINING     PRACTICE 


10 


uniform  grades.     In  general  throughout  the  district  haulage  entries 
are  too  narrow  for  safety,  and  are  not  kept  free  from  gob. 

Pit  cars  are  hauled  from  partiugs  to  the  bottom  by  main-and- 
tail  rope  in  one  mine,  by  standard  electric  locomotives  in  one,  by  a 
rack-rail  electric  locomotive  in  one,  and  by  mules  in  five.  Hauling 
from  face  to  partings  at  all  mines  is  done  by  mules.  They  are  kept 
in  good  condition.  The  rails  are  light,  varying  from  16  to  30  pounds 
on  the  main  haulage  and  from  12  to  16  on  the  cross  entries  and  in 
rooms.     Track  gages  vary  from  30  to  42  inches. 


Table  9 - 

—Haulage 

Rail  weight  in 

Pit  Cars 

c 

Kind  of 
haulage  in 
main  entry 

o  a> 

H 

.  o 

°  £ 

MM 

S.S 

pounds 

per  yard 

Q    & 

I5 

o  +j    • 

6 

CD 

be 

"s  i 

Second- 
ary 
haulage 

Weight 

in 
pounds 

Capac- 
ity in 
pounds 

Per  cent 
car  weigh 
total  load 

12 

Mule 

36 

16 

16 

1200 

1800 

1.5 

40.0 

13 

Electric 

locomotive 

2 

42 

30 

16 

2400 

4300 

1.8 

35.8 

14 

Mule 

32 

16 

12 

1100 

2600 

2.4 

29.7 

15 

Electric 
rack-rail 

locomotive 

2 

30 

30 

16 

2200 

3000 

1.4 

42.3 

Those  mines  working  in  the  lower  bench  where  narrow  and  low 
entries  are  necessary  have  light  pit  cars  of  small  capacity;  at  only 
one  mine  in  the  district  do  the  pit  cars  each  hold  two  tons.  The 
average  weight  of  these  cars  at  the  mines  examined  is  1,725  pounds; 
the  average  capacity,  2,925  pounds.  Hence,  an  average  of  37.1  per 
cent  of  the  weight  hauled  from  face  to  shaft  is  car  weight.  An  excess 
weight  of  car  is  carried  in  transporting  the  coal  in  the  mine.  With 
a  car  lighter  and  of  greater  capacity,  haulage  expense  could  be 
lessened. 

~No  figures  for  ton-mileage  of  locomotives  could  be  obtained. 

Table  9  gives  haulage  data  for  each  mine  examined. 

HOISTING 


No  mine  in  the  district  has  a  sufficiently  large  daily  production 
or  is  of  such  depth  as  to  necessitate  great  hoisting  speed,  so  that  the 
hoisting  equipment  has  no  unusual  features  of  size  or  arrangement. 
First  motion  hoisting  engines  are  in  use  at  all  mines  examined. 
Cylindrical  and  conical  drums  are  each  used  at  two  mines. 


20 


COAL    MINING    INVESTIGATIONS 


Table  10. — Hoisting 

o3 

4^ 

■S-S  w 

M*>,  cu 

Drum 

<D  C 

CX 

tH 

o 

C  F?  .£ 

d 

13 

is  o 

CD 

02 

3 

a 

<d 

Q 

CD 

c 

CD 
N 

Is? 

Hoisting  e 
— Size  of 
der  in  inc 

0) 

a 

4->   T_l 

CD  -M 

C    CD 
C    CD 

a  .a 

►3.9 

12 

150 

Yes 

125 

6  by  14 

No 

12  by  16 

Cylindrical 

4H 

8 

13 

1300 

Yes 

114 

9  by  20 

Yes 

18  by  36 

Conical 

7 

5 

14 

300 

No 

135 

7  by  12 

No 

18  by  36 

Cylindrical 

434 

8 

15 

800 

Yes 

160 

7  by  16 

No 

16  by  32 

Conical 

6 

6 

1.    Largest  diameter  if  conical. 


Caging  at  the  bottom  is  done  automatically  at  one  mine  and  by 
hand  at  three,  although  in  only  one  is  there  a  platform  cage  from 
which  the  cars  are  pushed  by  hand  at  the  tipple. 

Table  10  gives  hoisting  data  for  each  mine  examined. 


PREPARATION    OF    COAL 

PREPARATION  OF  COAL 


21 


The  sizes  of  coal  made  in  this  district,  which  differ  at  each 
mine  examined,  are  shown  in  Table  11.  Tipple  equipment  is  given 
in  Table  12. 

Table  11. — Sizes  of  coal  made 


No. 

Name 

Size. 

12 

Lump 

Over  2l/i  inches 
Under  234  inches. 

Screenings 

13 

Six-inch  lump 

Over  6  inches. 

Six-inch  egg 

Over  4  inches  and  under  6  inches. 

One-and-one-half  inch  lump  .  . 
Nut 

Over  \}/2  inches  and  under  4  inches. 
Over  \}/%  inches  and  under  \}/2  inches. 

Screenings 

Under  \}/%  inches. 

14 

Six-inch  lump 

Over  6  inches. 

One-and-one-half  inch  lump.  .  . 
Nut 

Over  13^  inches. 

Over  %  inch  and  under  1^  inches. 

15 

Six-inch  lump 

Over  6  inches. 

Six-inch  egg 

Over  3  inches  and  under  6  inches. 

Small  egg 

Over  2  inches  and  under  3  inches. 

No.  1  Nut 

Over  \l/i  inches  and  under  2  inches 
Over  l/i  inch  and  under  \l/i  inches. 
Under  l/i  inch. 

No.  3  Nut 

No.  5  Nut 

At  each  mine  examined  shaking  screens  are  used,  with  lengths 
varying  from  L6  to  42  feet,  and  with  widths  of  6  to  8  feet. 
They  have  an  inclination  of  either  -'5  or  4  inches  a  foot,  and  make1 
from  60  to  100  shakes  a  minute. 

At  the  one  mine  where  a  further  separation  is  made  after  pass- 
ing the  coal  over  a  shaker-screen  a  washery  of  the  Stewart  type  is 
installed.  A  description  of  this  washery  is  contained  in  Bulletin  69, 
(  !oal  Washing  in  Illinois,  published  by  the  Engineering  Experiment 
Station  of  the  University  of  Illinois. 


Table  12. — Tipple  equipment 

Sizing  screen 

Is  coal 
rescreened 
or  washed 

O  u  wj 

No. 

Inclina- 
tion 
(inches 
per  foot) 

Shakes 

per 

minute 

Coo 
<u       d 

0  a-q 

m 

12 
13 
14 
15 

32 
40 
16 
42 

6 

8 
6 
6 

3 

4 

4 

3 

90 

S4 

60 

100 

Neither 
Neither 
Neither 
Washedb 

70 
50 

See  foot  note'1 
()() 

a.  55  over  llA  inches. 

b.  Stewart  type  washery. 


22 


COAL    MINING    INVESTIGATIONS 


There  are  no  steel  tipples  in  the  district. 

The  power  plants  do  not  develop  large  horse-powers  and  are  of 
ordinary  construction  and  equipment.  x\ll  of  the  boilers  are  fire- 
tube  at  the  mines  examined.  Table  13  gives  power-plant  data  for 
each  mine. 


Table  13. — Power  Plant  Equipment 


Boilers 

Electric  Generators 

No. 

No. 

Total  H.  P. 

Average 
steam  pressure 

K.W. 

Voltage 

12 

2 
6 
9 
8 

300 
900 
450 
200 

100 

125 

80 

120 

13 
14 

225 

250 

15 

125 

250 

0F  PETROLEUM  C 


PUBLICATIONS  OF  THE  ILLINOIS  COAL  MINING 
INVESTIGATIONS 


Bulletin  1. 

Bulletin  2. 

Bulletin  3. 

Bulletin  4. 


Bulletin  5. 
Bulletin  6. 

Bulletin  7. 


Preliminary  Report  on  Organization  and  Method  of 

Investigations,  1913. 

Coal  Mining  Practice  in  District  VIII  (Danville), 
by  S.  O.  Andros,  1914. 

A  Chemical  Study  of  Illinois  Coals,  by  Prof.  S.  W. 
Parr,  1914. 

Coal  Mining  Practice  in  District  VII  (Mines  in  bed  6 
in  Bond,  Clinton,  Christian,  Macoupin,  Madison, 
Marion,  Montgomery,  Moultrie,  Perry,  Randolph, 
St.  Clair,  Sangamon,  Shelby  and  Washington 
counties),  by  S.  O.  Andros,  1914. 

Coal  Mining  Practice  in  District  I  (Longwall),  by 
S.  O.  Andros,  1914. 

Coal  Mining  Practice  in  District  V  (Mines  in  bed  5 
in  Saline  and  Gallatin  counties),  by  S.  O. 
Andros,  1914. 

Coal  Mining  Practice  in  District  II  (Mines  in  bed  2 
in  Jackson  county),  by  S.  O.  Andros,  1914. 


